D. H. Lewis, in his article ‘Ara Moana: Stars of the Sea Road’ in the July 1964 issue of the Journal of the Institute of Navigation (pp. 278–88), speculates on how the Polynesians could have navigated to known distant destinations, but does not explain how the knowledge of die distant destinations on which he relies for his theories was gained by the supposed navigators. Before anybody can navigate to somewhere, someone must first have gone there and come back. Lewis does not tell us how the Polynesians gained their knowledge of the existence, location and size of New Zealand and Hawaii, and of the currents on these courses, on their outward voyages of discovery, and then used this knowledge to get home again. His statement that ‘it seems probable that the Polynesians steered by horizon stars until the zenith star showed that they had reached the right latitude, and then turned east or west’, obviously has no application to voyages of discovery which by definition were made without prior knowledge of the existence, latitude or size of the objectives. The alternative supposition that the discoverers were able to keep account of their courses from bearings on stars which were reputedly aligned with the destinations and the home islands overlooks the fact that such star bearings gave no clue whatever to longitudinal displacement. There was no practicable method whereby the discoverers could have known the longitudinal relationships of their discoveries and their home islands.

I should like to make some comment on Captain Wylie's article in the January issue of the Journal (18, 27). While not disputing his arithmetic I should like to state that in practice true motion is much more effective than he implies. For two years I used an Escort true motion set on the Southampton, Cherbourg, New York run and I can say most unequivocally that ships did not have to be proceeding at 18 knots to get satisfactory trails on the 12-mile range scale. In fact one could see useful trails when ships were proceeding reasonably slowly.

In this paper, a condensed version of an address to the Annual Assembly Meeting of the Radio Technical Commission for Marine Services held at Boston on 31 March 1964, where world-wide shore-based harbour radar surveillance and guidance systems were discussed, the Harbour Master of Southampton reviews some of the more recent developments of the Port Operation and Information Service at Southampton. Developments in the port itself are first briefly described and then some implications for Southampton of the Rochdale Report and the Harbours Bill are examined. After an account of some improvements in radar equipment used in the port, some new ideas now being investigated are described.

This note provides some qualitative impressions of the need for precise navigation in the S.S.T. operation having due regard to performance and noise. It highlights the increased signific ance of the vertical plane, but quantitative conclusions as to horizontal ability cannot be made in the absence of knowledge of traffic amounts. It suggests that any tactical ‘chasing’ of noise reduction through performance variations not planned before flight is impracticable.

In common with other aircraft types, the S.S.T. has three distinct phases of flight apart from take-off and landing: climb to cruise altitude, cruise and descent. The S.S.T. climb is characterized by an acceleration phase dividing the subsonic portion of flight from the supersonic. Similarly, the descent profile includes a deceleration phase which restores flight to the subsonic region. Contained in these three phases of flight unique to the S.S.T.—acceleration, supersonic flight and deceleration—are some of the special factors affecting aircraft navigation.

Present criteria for aeronautical charts need further investigation in preparation for S.S.T. operations in respect to the facilities to be charted, the format for supplemental information, symbols and scale. For projection displays the negative presentation has decided advantages, while the use of colour has both advantages and disadvantages. Pre-loaded film cassettes for quick insertion into the dynamic display system can be maintained in libraries at S.S.T. terminals, which will also facilitate the frequent updating of the material.

In recent years the interest in dynamic map display systems has increased with the advent of S.S.T. planning and higher speed tactical aircraft. There are several approaches including a static chart with a mechanically driven ‘bug’, a moving paper chart with a static ‘bug’ in the form of a stylus, and several projected displays utilizing 35 mm. and 70 mm. film. This paper is chiefly concerned with projected displays.

I have read with interest Colin Jack-Hinton's article ‘The Use of Apparent Consistency in Errors of Latitude in the Identification of 16th and 17th Century Pacific Islands Discoveries’ in the July 1964 issue of the Journal of the Institute of Navigation (pp. 311–13). Jack-Hinton takes as his main target the two instances in my book The Discovery of the Pacific Islands in which I used persistent or steady southerly error as an aid to or basis for differentiations between atolls situated north and south of each other, namely Mendaña's Los Bajos de la Candellaria in reference to Roncador Reef and Ontong Java, and the first atoll seen by Le Maire after leaving the Home Islands in relation to Ontong Java and Nukumanu.

This paper was presented at the Eastbourne Convention in May 1964 and is based on data published by the author in recent issues of Meteor. Abh. Freie. Univ. Berlin.

A Joint Navigation Satellite Committee has been formed to determine the potential for a common satellite system to meet the needs of various agencies. As a potential aid to air traffic, satellites would appear to be most effectively used in cooperation with ground stations at which measurement and computation would be made. Possible user benefits include more effective communications, more reliable and possibly less expensive airborne navigation equipment, reduced diversions and delays, obstacle avoidance capability, more effective emergency warnings, and reduction of communication traffic. For the provider States benefits may include more reliable communications, reduction in number of control centres, improved data collection and distribution capability, reduction in number of facilities, and improved search and rescue capability. A systematic approach to long-range goals is indicated.

The whole question of Polynesian navigation is highly controversial. Dr. David Lewis's paper ‘Ara Moana: Stars of the Sea Road’, in the July issue of this journal, prompts me relate the story of Kau Moala in somewhat greater detail and to assess his achievements and motives, largely from his own account of his voyages.

Kau Moala was a Tongan Chief renowned for his epic feat of navigation which probably took place in the years just before 1800. The details come to us from a young English castaway named William Mariner, who spent several years in Tonga and knew Kau Moala personally. When Mariner got back to England his experiences were compiled by J. Martin and published by John Murray, London, in 1817. The work is generally known as ‘Mariner's Tonga’, the full title being An Account of the Natives of the Tonga Islands. The story of Kau Moala's famous Odyssey is given on pages 307–322 of volume I of the second edition, published in 1818. Mariner gives the Chief's name as Cow Mooaly.

The story starts with Kau Moala going from Tonga to Fiji to engage in some warlike adventures to enhance his prestige, as many another Tongan Chief had done before, and as several did later. After two years of fun and mischief he decided to return home, and set out in his large double canoe.

This paper, based on an earlier one presented at the Eastbourne Convention in May 1964, discusses certain aspects of S.S.T. performance and its bearing on the design of the air navigation system and on the air traffic control system. The requirement is established for a navigation system capable of directing the S.S.T. at minimum economic penalty and within the limits imposed by air traffic control and sonic boom considerations. The system should also be able to determine estimated time of arrival, fuel remaining, and altitude for any randomly chosen point along the flight path; to derive the time of arrival at a particular altitude and, for a selected time of arrival at a chosen position and altitude, give the deceleration and other necessary command information.

A paper by Captain J. F. Kemp under this title was published in the April number of this Journal together with some comments on these proposals. Further contributions to the discussion and a reply from Captain Kemp are printed below.

In the April issue of this Journal Captain Kemp has put forward a carefully considered proposal for making the Rule of the Road more effective. His proposal is well considered because he is aware of the audacity which its careful presentation conceals; he is also careful to suggest a change in the Rules only as a basis for discussion. His suggestion is precise, for it is simply to extend Rule 18 to all encounters, or in other words to require both vessels, when crossing or overtaking, to rotate the line of sight in the normal direction as required in Rule 18.

Captain A. F. Dickson's paper entitled ‘Recommended Routes for Ships in Congested Waters’ (Journal, 17, 217) suggests the introduction of a principle which I advocated in two previous papers, the second of which was presented at the Conferenza Intemazionale Sulla Disciplina dell ’uso del Radar, in Genoa, May 1957. Captain Dickson writes in his article:

It is therefore suggested that the measures to be taken should involve the application of one simple basic rule, that in all cases ships should keep to the starboard side of any channel and that traffic rounding a headland should be separated so that ships proceeding in opposite directions will have a port-to-port passing. In addition, wherever possible the different streams of traffic should be separated by a lane which would be a virtual no-man's-land between ships sailing in opposite directions. The lane might well be shown in colour and British Admiralty experience seems to indicate that purple is a good colour for chart usage, so the lane might be known as the “purple lane”.

In my works it was stated ‘Coastal radar navigation constitutes a very valuable means of making feasible an ordering of the natural traffic streams by regulating them according to the requirements of each area, following experience.

The fundamental necessities of efficient bridge and chartroom lighting, which matter appears to have been ignored even on many of the latest vessels, are the provision of:

1. Adequate illumination of all instruments in a uniform manner.

2. Efficient illumination of the chart.

3. A reduction of the high contrast of light values between chartroom and wheelhouse and the elimination of the sources of glare.

These three essentials can be combined to render the overall illumination of the navigating bridge efficient and practical, whether the ship has a separate chartroom and wheelhouse or the more modern chartroom and wheelhouse combined.

All bridge instruments, such as clocks, compasses, telegraphs and the numerous indicators, should be made to a uniform specification—all with ‘back’ or ‘edge’ illumination provided by red lamps. Where practicable these instruments should have black dials with white lettering. An extra refinement is to have the lettering painted with a luminous paint. Illuminating the instruments in this manner would also afford a certain amount of illumination to the otherwise dark navigating position. This would in turn tend to alleviate the high contrast of light between the chart area, which of necessity must be lit, and the total darkness outside.